Systems and methods for anesthetizing ear tissue

ABSTRACT

A system and method for use in iontophoretic anesthesia of a tympanic membrane are disclosed. The system generally includes an earplug and an electrode device. The earplug includes at least one sealing member for sealing the earplug in an ear canal. The method involves using the system on a human or animal subject.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.12/510,217, filed Jul. 27, 2009, now U.S. Pat. No. 8,452,392, whichclaims the benefit of U.S. Provisional Application No. 61/085,360,entitled “SYSTEMS AND METHODS FOR ANESTHETIZING EAR TISSUE”, filed onJul. 31, 2008, the entirety of which is incorporated by referenceherein.

FIELD OF THE INVENTION

The present invention is related to iontophoretic drug delivery methodsand systems. In particular, the present invention is related to noveland advantageous iontophoretic drug delivery methods and systems foranesthetizing ear tissue.

BACKGROUND OF THE INVENTION

Iontophoresis is a method for delivering a drug across a biologicalmembrane, such as the skin or, in the case of certain ear surgeryprocedures, the tympanic membrane (TM). By applying low-level electricalcurrent to a similarly charged drug solution, iontophoresis repels ionsof the drug, thus transporting them across the skin or other membrane.In ear procedures, attempts have been made in the past to useiontophoresis to anesthetize (or “numb”) a TM before placing an ear tubeacross it to treat chronic ear infections. For TM iontophoresis, a drugsolution is placed in an ear canal and current is applied to thesolution via an electrode, thus transporting the anesthetizing drugacross the TM.

Prior iontophoresis devices and systems have had limited success andoften cannot be used in all patients. Prior devices generally do notseal the drug solution in an ear canal, thus requiring a patient torecline and tilt his/her head during an iontophoresis procedure. Usingcurrently available iontophoresis methods, the patient must remainrelatively motionless in this reclined, head-tilted position for 5-15minutes while the iontophoresis procedure provides adequate anesthesiato the TM, which can be especially difficult for children. Furthermore,using the currently available systems it is only possible to anesthetizeone ear at a time, thus making iontophoretic anesthesia of both TMs in apatient a relatively lengthy, uncomfortable process.

Attempts have been made to administer iontophoretic fluid to a TM via anearplug designed to hold the fluid in the ear canal. For example, seeU.S. Pat. No. 5,674,196, issued to Donaldson et al. Earplugs such as theone described in Donaldson and other currently available earplugs,however, have a number of shortcomings. For example, most earplugs aredesigned to keep fluid out of the ear canal, rather than in the earcanal. Currently available and previously described earplugs generallydo not conform adequately to the curved anatomy of the ear canal andthus to not form a good seal in the ear canals of at least some (and insome cases all) patients. Thus, current earplugs typically allow fluidto leak out of the ear, which makes iontophoretic anesthesia deliverydifficult if not impossible with the patient in an upright position.Furthermore, previously described earplug devices for use iniontophoresis have not addressed issues such as bubble formation in theiontophoretic drug solution, which bubbles may interfere with thecontact between an iontophoretic electrode and the solution.

Therefore, it would be advantageous to have improved devices and systemsfor administering iontophoresis to a tympanic membrane. Ideally, suchdevices and systems would allow iontophoretic anesthesia to beadministered to a patient in an upright position. Also ideally, suchdevices and systems would facilitate bilateral, simultaneous TMiontophoresis. At least some of these objectives will be met by theembodiments of the present invention.

BRIEF SUMMARY OF THE INVENTION

In one aspect of the present invention, an iontophoresis system foranesthetizing the tympanic membrane of an ear of a patient may includean earplug, at least one flexible sealing element, and an electrodedevice. The earplug may include an distal portion, an proximal portion,a tube connecting the distal and proximal portions, and a side ventlocated at the tube or the proximal portion. The tube may have arelative stiffness that is less than that of the distal and proximalportions, the lower relative stiffness allowing the tube to conform tothe curvature of an ear canal. The flexible sealing element may becoupled to the tube of the earplug and may be shaped to form a sealwithin the ear canal. The electrode may include an electrode tip and anelongate shaft and may be slideably disposable within the tube of theearplug, wherein the electrode tip is sized to fit within the distalportion and slide within the tube.

In one embodiment the earplug may include a side vent in fluidcommunication with the tube for allowing venting of air and/or fluidfrom the tube. In one embodiment the distal portion may be rigidrelative to the tube. In one embodiment the distal portion may includean o-ring which seals against the electrode tip of the electrode devicein the advanced position. In one embodiment an outer diameter of theelectrode tip may be greater than an internal diameter of the o-ring,and the o-ring may be flexible to allow the electrode tip to pass intoit to a seal. In one embodiment the proximal portion may be rigid. Inone embodiment the proximal portion may include a luer fitting. In oneembodiment the at least one flexible sealing element may be umbrellashaped, with an open end of the sealing element facing the proximal endof the earplug. In one embodiment the at least one flexible sealingelement may include a distal sealing element and a proximal sealingelement, and a diameter of the proximal sealing element may be largerthan a diameter of the distal sealing element. In one embodiment each ofthe flexible sealing elements may be umbrella shaped, with an open endof each sealing element facing the proximal end of the earplug. In oneembodiment the electrode device may be malleable. In one embodiment theelectrode device may include a lumen. In one embodiment the system mayinclude an ear hook connected with the proximal portion of the earplug,the ear hook including a curved member for engaging a portion of the earand preventing dislodgement of the earplug after placement in the ear.In one embodiment the system may include an additional earplug and anadditional electrode for use in iontophoretic substance delivery to thetympanic membrane of the other ear of the human or animal subject. Inone embodiment the system may include a headset for coupling the earplugand the additional earplug while they are in the subject's ears.

In one aspect of the invention, a system for use in iontophoreticsubstance delivery to the tympanic membrane of an ear of a human oranimal subject may include an elongate, flexible tube with a proximalportion and a distal portion, a first flexible sealing element shapedlike an umbrella to form a seal within the ear canal, a second flexiblesealing element shaped like an umbrella to form a seal within the earcanal, a distal stiffening tube located within the distal portion of theelongate tube distal to the sealing member, a luer fitting coupled withthe proximal portion of the tube and including a side vent in fluidcommunication with the main lumen of the tube, and an electrode device.The flexible tube may include a main lumen extending therethrough. Thedistal portion may include an inner lip at the distal end of the distalportion and a sealing member proximal to the inner lip. The elongatetube may have sufficient flexibility to bend to conform to the shape ofan ear canal. The first flexible sealing element may be integral to anddisposed on an exterior of the elongate tube and being offset a distancefrom a distal most portion of the elongate tube. The second flexiblesealing element may be integral to and disposed on the exterior of theelongate tube and proximal to the first sealing element. The distalstiffening tube may prevent the distal portion of the elongate tube frombending. The electrode device may include an elongate shaft. Theelectrode tip may have a diameter greater than that of the elongateshaft. The electrode device may be movable within the tube lumen of theearplug from a retracted position, in which fluid may pass around theelectrode through the tube, to an advanced position, in which theelectrode tip may fit within the distal portion of the elongate tubebetween the inner lip and the sealing member to form a fluid tight seal.

In one aspect of the present invention, a method of anesthetizing atympanic membrane of an ear of a patient using iontophoresis may involvedelivering an anesthetizing drug solution to an ear canal of thepatient, inserting a iontophoresis device into the ear canal filled withanesthetizing drug solution, venting excess anesthetizing drug solutionthrough the lumen while inserting and while the electrode is in thefirst position, moving the electrode from the first position to thesecond position, and activating the electrode in the second position.The iontophoresis device may include an electrode moveable from a firstposition to a second position inside a lumen. The first position of theiontophoresis device may vent the ear canal. The second position of theiontophoresis device may seal the ear canal.

In one embodiment the method may further include verifying moving theelectrode from the first position to the second position using auditoryand/or tactile feedback. In one embodiment the method may includerepeating the method for a second ear of the subject. In one embodimenta head of the subject may be positioned in a reclined, tilted positionwhen delivering the drug solution to the ear canal and an uprightposition when activating the electrode. In one embodiment the method mayinclude repeating the method for a second ear of the subject, couplingthe earplugs with a headset coupled with the subject's head before orduring activating. In one embodiment the method may include deformingthe electrode to conform it to a shape of the ear canal.

In one aspect of the invention, a method of anesthetizing a tympanicmembrane of an ear of a patient using iontophoresis may includedelivering an anesthetizing drug solution to an ear canal of thepatient, inserting a iontophoresis device into an ear canal of thepatient, and activating the electrode. The iontophoresis device mayinclude an electrode inside a lumen. The iontophoresis device may sealthe anesthetizing drug solution and simultaneously vents excessanesthetizing drug solution past the electrode and through a seal insidethe lumen.

In one embodiment the method may include repeating the method for asecond ear of the patient. In one embodiment the patient may be in asideways position when delivering and an upright position whenactivating. In one embodiment the method may include deforming theelectrode to conform to the shape of the ear canal.

In one aspect of the invention, a kit for anesthetizing a tympanicmembrane of an ear of a human or animal subject using iontophoresis, thekit may include an earplug and a controller. The earplug may include adistal portion, a proximal portion, and a tube extending from the distalportion to the proximal portion, at least one flexible sealing elementextending from an outer surface of the tube and disposed closer to thedistal end than the proximal end, and an electrode device. The tube mayhave a stiffness less than a stiffness of the proximal and distalportions of the earplug. The electrode device may include an elongateshaft, and an electrode tip having a diameter greater than that of theelongate shaft. The electrode device may be movable within the tube ofthe earplug from a retracted position, in which fluid can pass aroundthe electrode through the tube, to an advanced position, in which theelectrode tip contacts an inner surface of the tube to prevent fluidfrom flowing through the tube. The controller may be electricallyconnectable to the electrode device.

In one embodiment the kit may include an additional earplug for theother ear of the subject, and an additional electrode device for theadditional earplug. In one embodiment the controller may connect to theelectrode device and the additional electrode device. In one embodimentthe kit may include a headset for placing on the subject's head andholding the electrodes and earplugs. In one embodiment the kit mayinclude a sufficient amount of drug solution to provide iontophoreticanesthesia to the tympanic membranes of both ears of the subject. In oneembodiment the kit may include a drug delivery device for delivering thedrug solution into the ear canals of the subject.

For further understanding of the nature and advantages of the variousaspects and embodiments, reference should be made to the followingdescription and accompanying drawing figures. Each of the figures isprovided for the purpose of illustration and description only and is notintended to limit the scope of the embodiments of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A shows a frontal view of an outer ear.

FIG. 1B shows a partial cross-sectional view of an outer, middle, andinner ear.

FIGS. 2A-2C show cross-sectional views of a system for anesthetizing atympanic membrane, according to various embodiments of the invention.

FIG. 2D shows a perspective view of a distal end of an earplug,according to one embodiment of the invention.

FIG. 2E shows a side view of an earplug, according to one embodiment ofthe invention.

FIGS. 2F and 2G show side views of systems for anesthetizing a tympanicmembrane, according to various embodiments of the invention.

FIG. 2H shows a system in use, according to one embodiment of theinvention.

FIGS. 3A-3C show partial cross-sectional views of a system foranesthetizing a tympanic membrane in use, according to variousembodiments of the invention.

FIG. 4 shows a kit for anesthetizing a tympanic membrane, according toone embodiment of the invention.

FIG. 5A shows a frontal view of a flexible sealing element, according toone embodiment of the invention.

FIG. 5B shows a side view of a flexible sealing element, according toone embodiment of the invention.

FIG. 5C shows a frontal view of a flexible sealing element, according toone embodiment of the invention.

FIG. 5D shows a side view of a flexible sealing element, according toone embodiment of the invention.

FIG. 5E shows a perspective view of a flexible sealing element,according to one embodiment of the invention.

FIG. 5F shows a front view of a flexible sealing element, according toone embodiment of the invention.

FIG. 6A shows a front view of an earplug including an ear hook,according to one embodiment of the invention.

FIG. 6B shows a front view of an earplug including an ear hook,according to one embodiment of the invention.

FIG. 6C shows a facing view of an earplug including an ear hook in use,according to one embodiment of the invention.

FIG. 6D shows a side view of a integrated ear bud, according to oneembodiment of the invention

FIGS. 6E and 6F show facing views of integrated ear buds in use,according to various embodiments of the invention.

FIG. 7A shows a perspective view of an earplug, according to oneembodiment of the invention.

FIG. 7B shows a perspective view of an extended portion for use in anearplug, according to one embodiment of the invention.

FIG. 7C shows a cross-sectional view of an extended portion for use inan earplug, according to one embodiment of the invention.

FIGS. 7D-7I show perspective views of extended portions for use in anearplug, according to various embodiments of the invention.

FIG. 7J shows an exploded view of an extended portion for use in anearplug, according to one embodiment of the invention.

FIG. 8A shows a side view of an expandable earplug, according to oneembodiment of the invention.

FIG. 8B shows a side view of an expandable earplug in use, according toone embodiment of the invention.

FIG. 9A shows a cross-sectional view of a foam plug device, according toone embodiment of the invention.

FIG. 9B shows a cross-sectional view of a foam balloon device, accordingto an embodiment of the invention.

FIG. 10A shows a cross-sectional view of speculum port, according to anembodiment of the invention.

FIG. 10B shows a cross-sectional view an alternative distal port,according to one embodiment of the invention.

FIG. 10C shows a perspective view of an alternative distal port,according to one embodiment of the invention

FIGS. 10D and 10E show a speculum port in use, according to oneembodiment of the invention.

FIGS. 10F through 10H show a speculum port in use, according to oneembodiment of the invention.

FIGS. 11 and 12 illustrate simplified support structures that are wornon a patient's head and support an iontophoresis system, according tovarious embodiments of the invention.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1A shows a view of an outer ear. The outer ear includes a majorelement known as the auricle or pinna 100. The outer ear serves as afunnel for directing sounds into the internal portions of the ear. Themajor physical features of the ear include the lobule 102, concha 104,anthelix 106, helix 108, scapha 110, triangular fossa 112, externalacoustic meatus 114, tragus 116, and antitragus 118.

FIG. 1B shows a cross-section of the inner and outer portions of theear. The pinna 100 is shown connected to the external auditory meatus118, or ear canal. The ear canal 118 is shown as a relatively straightpassage, but is often a more curved, tortuous passageway. The ear canal118 is connected to the middle ear 120, which includes the ear drum 122.The middle ear 120 in turn is connected to the internal ear 124. The eardrum 122 normally has a pocket of air behind an outer portion called thetympanic membrane. When the middle ear 120 becomes infected, fluidswells inside the ear drum 122. Fluid expansion causes extreme pain toone with a middle ear infection. Middle ear infections are common inyoung children. Suffering may be alleviated by puncturing the tympanicmembrane to evacuate the fluid, a treatment known as tympanocentesis.The patient may undergo general anesthesia prior to a tympanocentesisprocedure, but this is not preferred due to cost and health concerns. Asa preferable alternative, the tympanic membrane can be locallyanesthetized using iontophoretic drug delivery. Thus the patient may betreated while awake. Devices and methods for locally anesthetizing thetympanic membrane are disclosed in co-assigned patent applications U.S.Ser. No. 11/962,073 and U.S. Ser. No. 11/749,729, the entireties ofwhich are incorporated by reference herein.

FIG. 2A shows an iontophoresis system 200 for anesthetizing a tympanicmembrane, according to one embodiment of the invention. The system 200includes an earplug 202 and an electrode device 206. The earplug 202 mayinclude a flexible sealing element 204, a distal portion 208, a proximalportion 210, and a tube 212 connecting both. The tube 212 is relativelymore flexible, in terms of resistance to bending, than the distalportion 208 and proximal portion 210. This is particularly advantageousbecause the ear canal often is a tortuous passage, which requires thatthe distal portion 208 and proximal portion 210 to be placed at oppositeends of the tortuous passage. The earplug 202 will preferably bend andmatch the form of the tortuous passage without blocking the tube 212.Alternatively the earplug 202 may be pre-bent or pre-formed in apreferred shape to match a tortuous passage of an ear canal. To achievea desired flexibility, the earplug 202 can be formed from a flexiblepolymer material, such as silicone.

The distal portion 208 can include a rigid member 214. The rigid member214 can generally be cylindrical or tube shaped and include an inner lip216 that prevents the electrode device from exiting the distal portion208. The rigid member 214 can be constructed from a metal or polymerwhich adds structural integrity to the distal portion 208. The rigidmember 214 provides the distal portion 208 to have a greater stiffnessthan the tube 212, such that the distal portion 208 will maintain shapewhen passed through a tortuous passage. The rigid member 214 can bebonded or molded into the distal portion 208 Alternatively, the rigidmember 214 is integral to the distal portion 208 as a portion of wallthickness which is greater than the wall thickness of the tube 212.

The distal portion 208 can also include an o-ring 218. The o-ring 218fluidly seals the electrode device 206 inside the distal portion 208.The o-ring can be bonded or molded into the distal portion 208, oralternatively be integrally formed between the distal portion 208 andthe tube 212. The o-ring 218 can be designed to allow fluid to pass whenexperiencing a higher than atmosphere pressure load, e.g. the pressurewhich occurs from inserting the system 200 into a fluid filled ear. Forexample, the o-ring 218 can be designed as a duck-bill seal which opensinto the proximal direction. It has been found in testing that 2.2 cm ofH2O is a good value for threshold o-ring pressure relief.

The proximal portion 210 may be stiffer than the tube 212 such that theshape of the proximal portion 210 will be maintained when being insertedinto a tortuous passage. The proximal portion 210 can include a sidevent 220. The side vent 220 functions to vent excess fluid out of theear, which vents from the proximal portion 208 and through the tube 212.Alternatively the side vent 220 may be located about the tube 212. Theproximal portion 210 may include a luer fitting with a fluid tightfitting 222 to interface with the electrode device 206, as shown. Theproximal portion may include a barbed portion 222 to interface with thetube 212. Alternatively the proximal portion 210 may be integrallyformed into the tube 212, and maintain rigidity through moldedstiffening inserts or by use of thick wall sections.

The flexible sealing elements 204 are used to form a fluid tight sealbetween the system 200 and the ear canal. The flexible sealing elements204 are generally flexible and deform and conform to the shape of an earcanal to form a fluid tight seal. Two flexible sealing elements 204 areshown, however only one is required and more than two may be used. Thefirst sealing element 204 a may be oval-umbrella shaped and integrallyformed into the tube 212 and distal portion 208, as shown. Alternativelythe flexible sealing elements 204 may be pyramidal (three-sided) ortriangular in shape. It has been found that the ear canal often has anoval or triangular cross-section. An offset 226 between the firstflexible sealing element 204 a and the distal most portion of the system200 is preferred. The offset 226 provides extra volume inside the earfor air bubbles to reside, thus preventing air bubbles from blocking thedistal portion 208. The second sealing element 204 b may be larger thanthe first sealing element and integrally formed into the tube 212, asshown.

In an alternative embodiment, the flexible sealing elements 204 caninclude adhesive elements to promote a fluid tight seal between thesurface of the sealing elements 204 and the ear canal. For example, anadhesive layer can be used on the external (i.e., canal facing) surfacesof the first sealing element 204 a and/or the second sealing element 204b. The adhesive layer can be covered by a backing tape, which can beremoved prior to insertion into the ear canal. A variety of adhesivescan be used, for example, a temperature dependent adhesive which is onlymildly tacky at room temperature and becomes extremely tacky afterinsertion through heating by the ear canal. A temperature dependentadhesive may allow for placement and replacement in the complex anatomyof the ear to minimize patient discomfort. The earplug 202 can be cooledby a cool compress to reduce tackiness and allow removal of the earplug202. Examples of adhesive elements include the Eakin Cohesive® sealmanufactured by CovaTec, Inc., and the Pre-Po® drape manufactured byLandec Labs, Inc. Alternatively, a temperature dependent adhesive whichis extremely tacky at body temperature and becomes mildly tacky whenheated to a temperature above body temperature can be used. In thisembodiment, heat can be applied by a warm compress to reduce tackinessand allow removal of the earplug 202.

The electrode device 206 includes an electrode tip 228, an elongateshaft 230, and a proximal connector 232. The electrode tip 228 may becylindrically shaped to match the interior portion of the distal portion208. The electrode tip 228 is generally shaped to form a seal within thedistal portion 208 between the inner lip 216 and the o-ring 218. Theelectrode tip 228 is also sized to be slideably disposable within thetube 212. The electrode tip 228 is preferably constructed from silver(99.9% pure). It has been found that a pure silver electrode tip 228,which may include an oxidized layer on the electrode tip 228, aids inthe iontophoresis procedure. Prior devices utilized stainless steel orgold electrodes which have the tendency to cause electrolysis of aniontophoresis fluid, for example lidocaine, which in turn lowers the pHvalue and causes discomfort. The silver electrode relatively reduceselectrolysis and prevents thus discomfort. Alternatively the electrodetip 228 may include a silver coating over a different metal such asstainless steel.

The electrode tip 228 is shown as a cylindrical shaped metal mass,however in alternative embodiments the electrode tip 228 can havedifferent configurations to increase surface area and promoteiontophoresis. For example, a plurality of silver wires configuredsimilarly to a brush can be used. In another embodiment, a plurality ofconcentric hypotubes with staggered diameters can be used. In anotherembodiment, a silver mesh mass configured similarly to steel wool can beused. In another embodiment, a molded polymer matrix plug with arelatively large surface area (e.g., sponge like) and a gold or silverplating or deposition can be used. In another embodiment, a metal-coatedwoven fabric can be used, with or without an outer insulator dependingon size. In another embodiment, a cylindrical body with an internal anddistally exposed honeycomb can be used. In another embodiment, a silverfoil coil can be used. In another embodiment, a recessed plug sized(i.e., smaller diameter) such that the plug has exposed sides can beused. In another embodiment, the elongate shaft 230 can be used as theelectrode, either as a tube or wire, and using a proximal seal in thetube 212. In another embodiment, a mass with a plurality of petals orbranches (e.g., flower shaped) which are integrated into the surface ofa flexible sealing element 204 can be used. In another embodiment, asoft flexible bag, with an insulative outer surface and a silver coatedinner surface, extending distally from the distal portion 208 can beused. In another embodiment, one or more cavities, which include metalcoated surfaces, in the distal portion 208 may be used. In anotherembodiment, the electrode tip 228 can include holes and/or a texturedsurface (e.g., crosshatched, etched, sandblasted) to increase surfacearea. In another embodiment, the electrode tip 228 can include multiplemetal types with one metal being a sacrificial anode (e.g., zinc). Inanother embodiment, a conveyor system (e.g., a metal coated flexiblebelt) which can be actuated to supply a fresh electrode surfacethroughout the procedure can be used. In another embodiment, the tube212 can include wiping elements which clean the surface of an electrodewhen turned, in order to supply a fresh electrode surface throughout theprocedure. In another embodiment, the electrode tip 228 can include aprotective coating to help prevent corrosion.

The electrode tip 228 may be attached to the elongate shaft 230 bysoldering or welding. The elongate shaft 230 may be constructed from thesame materials as the electrode tip 228. The elongate shaft 230 may alsoinclude a lumen to allow the passage of fluid. The elongate shaft 230 ispreferably malleable to allow a user to pre-bend the elongate shaftbefore inserting the system 200 into an ear canal. The earplug 202 mayalso be placed prior to the electrode device 206, and thus the electrodedevice 206 may be shaped to conform to the pre-inserted and deformedearplug 202. The proximal connector 232 is shaped to fluidly seal withthe proximal portion 210. The proximal connector 232 is furtherelectrically connected to a wire 234 to provide energy to the electrodedevice 206.

FIG. 2B shows the iontophoresis system 200 in a first position,according to one embodiment of the invention. The electrode device 206is shown with the electrode tip 228 in a proximal position inside thetube 212. In the first position the distal portion 208 is in fluidcommunication with the tube 212. In the first position fluid may passthrough the distal portion 208 and out through the vent 220, as shown bythe directional arrow.

FIG. 2C shows the iontophoresis system 200 in a second position,according to one embodiment of the invention. The electrode device 206is shown with the electrode tip in a distal position within the distalportion 208. The electrode device 206 may be forcibly passed by theo-ring 218 which may cause an audible ‘snap’. Thus the electrode device206 may be moved from the first position to the second position with anaudible confirmation. In the second position the open distal position208 is closed and is no longer in fluid communication with the tube 212.In an alternative embodiment the o-ring 218 may allow fluid to passthrough when fluid pressures inside the ear canal exceed a threshold.

FIG. 2D shows an alternative embodiment of the iontophoresis system 200.In this embodiment, the offset portion 226 and distal portion 208 eachinclude a plurality of aligned holes 236 which are placed proximatelybehind the inner lip 216. Four holes 236 are shown, however, more orfewer holes may be used in alternative embodiments. The holes 236 mayhave any of a number of suitable sizes, for example in one embodimentthey may have diameters of about 0.025 inches each. The holes 236 canreduce trapped volume of the drug solution and allow more surface areaof the electrode tip 228 to be exposed, which in turn can decrease thevoltage requirement for an iontophoresis procedure. An iontophoresisprocedure gradually causes the electrode tip 228 to corrode, and thusdraw more voltage from an iontophoresis system as the electricefficiency of the electrode tip decreases. It has been experimentallyshown in cadaver testing that the holes 236 can reduce voltagerequirements by approximately two-thirds over a period of 10 minutes, ascompared to a system 200 without holes 236. Thus, use of the holes 236can prevent system checks and voltage spikes from occurring. Systemchecks are instances where the iontophoresis system cannot meet thevoltage demands of the corroded electrode tip 228, and thus theiontophoresis procedure can be unintentionally halted. Voltage spikescan cause discomfort to the patient.

FIG. 2E shows an alternative embodiment of the iontophoresis system 200.In this embodiment the system 200 remains largely as described above,however, a bag 238 is attached to the distal end of the system 200. Thebag 238 may be constructed from a pliable substance such as a thinpolymer or woven material. The bag 238 can have an outer adhesivesubstance, such as the adhesive members described herein. Organicdebris, such skin flakes or wax can be dislodged during the insertionand/or iontophoresis process. The debris can stick to the electrode ofthe system 200 and reduce the active surface area of the electrode. Inuse, the system may be inserted into the ear and the bag 238 can beadhered to the surfaces of the ear canal leading up to the ear drum 122.The bag 238 can be expanded against the ear canal by physical probingwith a probe such as a cotton swab, or inflated using expanding foam ora balloon. In some embodiments the bag 238 can be a double walledballoon. The bag 238 can prevent debris from sticking to the electrodeby presenting a physical barrier between the ear canal and theelectrode. The bag can also reduce the loss of drug solution, as thewalls of the ear canal will be blocked from absorption of drug solution.

FIGS. 2F through 2H show alternative embodiments of the iontophoresissystem 200. In these embodiments, the system 200 remains largely asdescribed above, however, a flexible electrode 240 extends from thedistal end of the system 200. The flexible electrode 240 can include aninsulative side 242, and a conductive side 244 with an exposed metal(e.g., silver) portion. The flexible electrode 240 can be constructedfrom a flexible polymer material, such as polyimide, and coextruded witha metal strip. The flexible electrode 240 can be configured as asingular looped band with the exposed metal portion on the inner portionof the loop. Alternatively, more than one band can be used, as shown byflexible electrode 246 of FIG. 2G. The length of extension of theflexible electrode 240 can be adjusted according to a specific patient'sanatomy. In use, the flexible electrode 240 can come into contact withthe ear canal, as shown in FIG. 2H, without causing shocks, as theconductive side 244 does not contact the ear canal. The flexibleelectrode 204 can deflect from the ear canal due to its flexible nature.The flexible electrode 240 provides a larger electrode surface area fora more efficient iontophoresis procedure. The large electrode surfacearea can also reduce bubble formation in the drug solution.

FIGS. 3A through 3C show a method of using the iontophoresis system 200for anesthetizing a tympanic membrane of an ear of a patient, accordingto one embodiment of the invention. A cross-section of an ear 300 of apatient is shown. The patient may initially be placed on his or her sidewith the treatment ear facing upwards. Iontophoresis fluid 302 is theninjected inside the ear canal, as shown. An earplug 304 is then insertedinto the filled ear canal to seal the iontophoresis fluid within the earcanal. The earplug 304 is generally as described in the embodimentsherein. The earplug 304 may optionally be primed with iontophoresisfluid 302 prior to inserting it into the ear canal.

In FIG. 3B, an electrode device 306 is inserted into the insertedearplug 304. The electrode device 306 may be malleable and optionallypre-bent prior to insertion. The electrode device 306 may make anaudible noise when it is fully inserted into the earplug 304, thusgiving the user an audible signal to verify that the electrode device isproperly placed. As the electrode device 306 is fully inserted, pressurewill increase inside the ear canal and excess fluid 308 will vent outthe back of the plug and immediately balance the fluid pressure with theatmosphere, as shown. This is extremely advantageous, as even a slightpressure increase can cause great pain to an infected ear. After theelectrode device 306 has been fully inserted, it may be energized totreat the patient. The other ear may also be treated as describedherein.

In an alternative embodiment the electrode device 306 may be partiallyinserted into the earplug 304 in a first position, for example theelectrode tip 228 in the tube 212, during the initial insertion into theear canal. After the earplug 304 has been placed the electrode device306 may be moved from the first position to a second position (e.g.working position) of full insertion into the earplug 304.

In yet another alternative embodiment the electrode device 306 may befully inserted into the earplug 304 prior to insertion into the earcanal. As the earplug 304 is inserted into the ear canal, pressure willincrease inside the ear, and simultaneously the pressure will berelieved through a seal within the earplug 304 which vents excess fluidwhen the pressure exceeds a certain threshold. This embodiment isadvantageous because it does not require a user to move the electrodewhile the earplug is placed within the ear.

FIG. 3C shows the ear, and thus the patient, in an upright position. Thedevice 304 includes an offset 310 from the electrode which causes airbubble 312 to move to the position shown. The offset 310 prevents airbubbles from resting directly or partially on the electrode, which wouldcause a partial or ineffective treatment. The offset 310 is advantageousbecause it allows the system 200 to be used in an upright position, andaccordingly both ears may be treated simultaneously.

In an alternative embodiment the patient may be in an upright positionprior to insertion of iontophoresis fluid 302 or the earplug 304. Theearplug 304 is first inserted into the ear canal with the electrodedevice 306 fully inserted. In this embodiment the electrode device 306includes a separate lumen for filling the ear canal. Iontophoresis fluid302 is injected through the electrode device 306 to fill the ear canal.When the ear canal is filled with iontophoresis fluid 302, pressure willincrease inside the ear, and simultaneously the pressure will berelieved through a seal within the earplug 304. Thus, excess fluid isvented when the pressure exceeds a certain threshold. This embodiment isadvantageous because one or both ears may be filled simultaneously ifrequired, and also while the patient is in an upright position.

In an alternative embodiment, a proximal sealing material can be appliedafter the device 304 is placed as shown in FIG. 3C. The sealing materialcan be made from soft, putty-like material, for example, a bone wax(e.g., beeswax, paraffin, or isopropyl palmitate) can be used. Thesealing material can be used separately, or as a sealably attachedmember to the device 304, for example, as a proximally (e.g., betweensealing member 204 b and side vent 220 of FIG. 2A) located disc. Thesealing material can be shapeable when heated to body temperature. Inuse, the sealing material can be pushed and formed into the concha andexternal ear anatomy after the device 304 is placed as shown in FIG. 3C.The sealing material can conform to the complex anatomy of the outer earand ensure secure fixation. The sealing material can also provide afluid tight seal which allows the use of a slightly smaller sized device304, which in turn allows a faster and less traumatic device insertioninto the ear canal, as the sealing material is providing the primaryseal instead of the device 304.

Alternatively, a fabric patch can be used in place or in conjunctionwith the sealing material. The fabric patch can have a disc shape and besealably attached to the device 304, as a proximally (e.g., betweensealing member 204 b and side vent 220 of FIG. 2A) located disc. Thefabric patch can include an adhesive, such as the temperature dependentadhesives described herein. The fabric patch can alternatively be use aconventional adhesive, for example, as used in Nexcare™ Tegaderm™Transparent Dressing manufactured by 3M, Inc. In use, the fabric patchcan be pushed and formed into the concha and external ear anatomy afterthe device 304 is placed as shown in FIG. 3C. The fabric patch canprovide both a fluid seal and ensure secure fixation. Thus, the fabricpatch can also be used with a smaller than standard device 304.

FIG. 4 shows a kit 400 for anesthetizing a tympanic membrane of an earof a patient using iontophoresis, according to one embodiment of theinvention. The kit includes a system 402, which is substantially similarto the devices disclosed herein. Each system 402 includes an earplug 404and an electrode device 406. As shown, various sized earplugs arepossible. The kit 400 also includes a controller 408, which includes areturn electrode 410, and is electrically compatible with the system402. The controller 412 provides electrical power to the system 402 foran iontophoresis procedure. Examples of compatible controllers are shownin previously incorporated by reference and co-assigned U.S. applicationSer. No. 11/962,063.

FIGS. 5A and 5B shows frontal and side views respectively, of a flexiblesealing element 500 in an umbrella like configuration, according to oneembodiment of the invention. Flexible sealing element 500 includesintegral ribs 502 or spokes. The integral ribs 502 allow remainingportions 504 of the flexible sealing element 500 to be thinner than theribbed portions, and thus the flexible sealing element 500 deforms veryreadily. Thus a device which incorporates the flexible sealing element500, for example system 200, may achieve a seal within an ear canal withless force than a sealing element lacking the integral ribs 502.Alternatively, the integral ribs 502 may be located on the internalportion of the flexible sealing device 500.

FIGS. 5C and 5D show frontal and side views respectively, of a flexiblesealing element 506, according to one embodiment of the invention.Flexible sealing element 506 includes cut out portions 508. The cut outportions 508 feature a thin web of material. The cut out portions 508are thinner than the remaining portion 510 of the flexible sealingelement 506, and thus the flexible sealing element 506 deforms veryreadily. Thus a device which incorporates the flexible sealing element506, for example system 200, may achieve a seal within an ear canal withless force than a sealing element lacking the cut out portions 508.Alternatively, the cut out portions 508 may be located on the internalportion of the flexible sealing device 506.

FIGS. 5E and 5F show perspective and front views respectively, of aflexible sealing element 510, according to one embodiment of theinvention. Flexible sealing element 506 is pyramidal or triangularlyshaped, as shown. The flexible sealing element 506 includes three sidesfor sealing an ear canal. Ear canals do not have circular cross-sectionsand often are triangular in shape. Thus the flexible sealing element 510may fit in and seal an ear canal with great effectiveness.

FIGS. 6A and 6B show rear and side views respectively, of an earplug600, according to one embodiment of the invention. Earplug 600 includesmain body 602, which may include a tubular element and at least oneflexible sealing element as generally described herein. The earplug alsoincludes ear hook 604. Previous devices have used retention mechanismssuch as ear muffs or headphone style configurations to help retainearplugs. These prior devices tend to cause annoyance and discomfort tothe user (e.g. small children) and result in patient induced disruptionsto the iontophoresis treatment. The ear hook 604 may be formed from aflexible polymer such as silicone, and also may be integral to theearplug 600. The ear hook 604 may also include a skeleton likeconstruction, of a flexible polymer wrapped around a core (e.g. a wire).The core may be malleable in order for the ear hook 604 may be shaped tomatch the profile of a specific ear. Alternatively the core may beresilient and help place a constant force from the outer ear onto theearplug 600.

FIG. 6C shows the earplug 600 in use, according to one embodiment of theinvention. The ear hook 604 is designed to wrap around the crux of ahelix 606 of an ear. The ear hook 604 is advantageous over other priordevices because it has relatively low mass and thus does not feel overlyintrusive to a patient.

FIG. 6D shows an integrated ear bud 608, according to one embodiment ofthe invention. The ear bud includes a main body 610, which includes apower source and control unit. The control unit can have thefunctionality of the control unit 412 of FIG. 4. The main body 610 caninclude control buttons for starting or stopping an iontophoresisprocedure. The main body 610 can include one or more adhesive patches.The ear bud 608 also includes a malleable bridge 612 which has a curvedprofile. The malleable bridge 612 can be constructed from a flexiblepolymer, such as rubber, and can have a malleable metal core. An earplug614 can be pivotably connected to the malleable bridge 612. The earplug614 can generally share the construction of the earplugs disclosedherein. A cable 616 leads from the main body 610 and connects to areturn electrode 618. The return electrode 618 can include a snapelement to allow connection to other return electrodes.

FIG. 6E shows the integrated ear bud 608 in use, according to anembodiment of the invention. The main body 610 can be placed behind thehelix as shown, and can be temporarily adhered to the patient's skin.The malleable bridge 612 wraps around the helix and the earplug 614 isinserted into the ear canal. The integrated ear bud 608 supports theearplug 614 to prevent unwanted movement and to also provide a constantmounting force to help ensure a fluid tight seal. The malleable bridge612 can be adjusted to provide more or less mounting force. The earplug614 can be rotated so that the integrated ear bug 608 can be used oneither ear. The return electrode 618 can be adhered to a portion of thepatient's skin to provide an electrical return path for the controlunit. As the integrated ear bud 608 includes an integrated control unit,the patient can be free to move during the procedure.

FIG. 6F shows an integrated ear bud 620 in use, according to oneembodiment of the invention. The integrated ear bud 620 is configuredsimilarly to the ear bud 608 of FIG. 6D, however, a control unit 622 isseparately housed with a return electrode patch. The integrated ear bud620 also includes a malleable body 624 which completely surrounds thehelix of the ear. The malleable body 624 can be constructed from aflexible polymer, such as rubber, and can have a malleable metal core.The malleable body 624 can be adjusted to fit various ear anatomies toprevent unwanted movement and to also provide a constant mounting forceto help ensure a fluid tight seal.

FIG. 7A shows an earplug 700, according to one embodiment of theinvention. Different regions of the ear anatomy have different levels ofelectrical resistance. Electrical current flows preferentially throughareas of lower resistance. For example the tympanic membrane has a lowerresistance than areas of cartilage in the ear canal. It is desirable toprevent unwanted electrical contact to higher resistance areas, and alsodesirable to limit the amount of current delivered for patient comfort.Placing the electrode as close to the tympanic membrane as possiblehelps achieve a positive outcome because it helps reduce overall currentdelivery. However, the ear canal is known to be tortuous and thusplacing an electrode near the tympanic membrane is difficult withoutcontacting other areas of the ear. The earplug 700 solves thesedifficulties.

The earplug 700 includes a sealing body 702 for sealing the earplug 700in an ear canal. The sealing body 702 may include the construction ofother similar earplugs disclosed herein. The sealing body 702 may or maynot include lumens and vents for filling the ear canal. The earplug 700includes an insulation body 704 which runs throughout the sealing body702. The extended portion 706 of the insulation body 704 houses anelectrode 708. The extended portion 706 is advantageous because itextends the electrode 708 well past the sealing body and closer in useto the tympanic membrane. The distal portion 706 also may contactportions of the ear canal while still providing insulation for theelectrode 708.

FIGS. 7B and 7C show perspective and cross-sectional views respectively,of an alternative extended portion 710, which may be used with forexample the earplug 700 shown in FIG. 7A. The extended portion 710features multiple slits 712 which provide fluid access to the innerelectrode 714. The extended portion 710 may be formed from a hypotubewhich has been cut and coated with an external insulating barrier. Theextended portion is advantageous because it reduces the amount of partsneeded, and also lowers current density by using a relatively largesurface area for the electrode 714. Lower current density has been foundto increase patient comfort. Alternatively the domed portion may be 710may be removed and also more or less slits 712 than shown may be used.

FIG. 7D shows a perspective view, of an alternative extended portion710, which may be used with for example the earplug 700 shown in FIG.7A. The extended portion 710 includes insulating portions 716 a, 716 b,and electrode 718. The electrode 718 may be constructed from a superelastic alloy, such as nickel titanium. And thus when electrode 716 acomes into contact with portions of the ear canal, the electrode 718will easily deflect as needed. The electrode 718 may be longer thanshown, and includes multiple insulating portions 716 b, to furtherextend the electrode 718 near the tympanic membrane.

FIG. 7E shows a perspective view, of an alternative extended portion720, which may be used with for example the earplug 700 shown in FIG.7A. The extended portion 720 is of a hypotube construction similar towhat is shown in FIGS. 7B and 7C. The extended portion 720 includesmultiple drilled holes 722 which allow fluid communication with an innerelectrode portion 724, shown by the darker areas. The extended portion720 may be formed from a hypotube which has been cut and drilled, andcoated with an external insulating barrier.

FIG. 7F shows a perspective view, of an alternative extended portion726, which may be used with for example the earplug 700 shown in FIG.7A. Extended portion 726 may be configured as an easily deformable butresilient basket. When the extended portion 726 comes into contact withportions of an ear canal, it will easily deflect. The extended portion728 is constructed from an outer insulating material 728 and an innerconducting portion 730. The extended portion 726 may be constructed froma super elastic material such as nickel titanium, and of thinproportions, for example less than 0.005 inches thick.

FIG. 7G shows a perspective view, of an alternative extended portion732, which may be used with for example the earplug 700 shown in FIG.7A. The extended portion 732 includes an outer insulating member 734 anda plurality of electrodes 736. The plurality of electrodes 736 areextended within the insulating member 734. This configuration isadvantageous because it greatly increases the conductive surface areaand thus helps reduce current density. This configuration also directscurrent flow in a distal direction towards the tympanic membrane when inuse.

FIG. 7H shows a perspective view, of an alternative extended portion738, which may be used with for example the earplug 700 shown in FIG.7A. The extended portion 738 is similar to the extended portion shown inFIG. 7F. However the electrodes 742 are insulated up until a distal mostpoint as shown. This configuration also directs current flow in a distaldirection towards the tympanic membrane when in use.

FIGS. 7I and 7J show perspective and exploded views respectively, of analternative extended portion 744, which may be used with for example theearplug 700 shown in FIG. 7A. The extended portion 744 includes a coiledconfiguration as shown, which further includes a laminated construction.The laminated construction includes an outer insulating member 746, aconducting member 748, and a inner insulating member 750. The innerinsulating member 750 includes openings 752 which expose the conductingmember 750. The extended portion 744 may be constructed from aninitially coated flat wire, which is subsequently cut on one side toform openings 752, and further coiled into shape.

FIGS. 8A and 8B show side and operational views respectively, of anexpandable earplug, according to one embodiment of the invention.Earplug 800 includes an outer expandable portion 802 and an expander804. The outer expandable portion 802 and the expander may be connectedinternally near the distal end of the earplug, as shown. The expander804 is slideable within the expandable portion, and may be withdrawnproximally to force the outer expandable portion to expand into a secondconfiguration, as shown in FIG. 8B. The outer expandable portion 802 maybe constructed from a soft polymer, for example silicone. Thisconfiguration is advantageous because it allows for a precise fit withinthe anatomy of a specific ear, and also allows deeper positioning.

FIG. 9A shows a foam plug device 900, according to one embodiment of theinvention. The foam plug device 900 includes an electrode 902 and aperforated tube 904 attached to the electrode 902. A foam plug 906surrounds the electrode 902. The foam plug 906 can have a cylindrical orconical shape, and can be constructed from open celled foam. Theelectrode 902 can be constructed from a malleable metal (e.g., silver)solid or stranded wire, or a solid or perforated tube, and includeinsulation 908 leading from the proximal end of the perforated tube 904.An electrical connector (not shown) can connect to the proximal end ofthe electrode 902. The perforated tube 904 can be constructed from aflexible and insulative or conductive material, and generally includesperforations throughout. The foam plug device 900 can also includeadditional sealing elements (not shown) and/or adhesives, as describedherein. In use, the foam plug 906 can be compressed, inserted into anear canal, and then allowed to expand to seal the ear canal. Drugsolution can be introduced into the ear canal prior to insertion of thefoam plug device 900, or after due to the open cell nature of the foamplug 902. The porosity of the foam plug can allow drug solution contactthroughout the length of the perforated tube 904, thereby increasingelectrode surface area via the perforations in the perforated tube 904.The porosity of the foam plug can also prevent pressure build-up duringan iontophoresis procedure.

FIG. 9B shows a foam balloon device 910, according to one embodiment ofthe invention. The foam balloon device 910 includes an electrode 912.The electrode 912 can be constructed from a malleable metal (e.g.,silver) solid or stranded wire, or solid or perforated tube. In oneembodiment, the electrode 912 may include an outer lumen (not shown)which can be manufactured from a polyether block amide (e.g., Pebax®55D) with an inner diameter of about 0.060″ and an outer diameter ofabout 0.072″. An electrical connector (not shown) can connect to theproximal end of the electrode. The electrode 912 can also include adistal end with an expanded insulator surrounding a plurality of wirestrands. A foam plug 914 surrounds the electrode 912. The foam plug 914may be constructed from open celled foam. A polyether foam (EC85HDE)with a density of 5 lb/ft³, and manufactured by Foamex Innovations, Inc.has been found to be suitable. The foam plug can have a cylindricalshape with an outer diameter of 5-15 mm, and an inner diameter of 2.5mm. Outer diameters of 8.3 mm and 11 mm have been used. The foam plugcan have other shapes, such as conical. The foam plug is encased by adouble walled balloon 916. The double walled balloon 916 can beconstructed from a compliant, semi-compliant, or non-compliant material.In one embodiment, the double walled balloon 916 can be formed by dipcoating a shaped mandrel with a silicone, such as MED10-6400manufactured by NuSil Technology LLC. The double walled balloon 916 canthen be adhered to a portion of the electrode 912 and then partiallyinverted to create a double wall. The foam plug 914 can then be insertedinto the space between the walls. The distal portion of the balloon 916can be connected to a suction coupler 918, such as T connector 88207available from Qosina Corp.

In use, a vacuum can be applied to the suction coupler 918, which causesthe foam plug 914 to collapse. The foam balloon device 910 can then beinserted into an ear canal. Once in place, the vacuum can bediscontinued which causes the foam 914 to expand. The foam 914 expansionpresses the double walled balloon 916 in contact with the ear canalwalls to fluidly seal drug solution within the ear canal. As positiveair pressure is not used to inflate the double walled balloon, thedanger of balloon rupture is negated. Vacuum may be reapplied tore-collapse the foam 914 in order to aid in removal.

FIG. 10A shows a speculum port 1000, according to an embodiment of theinvention. The speculum port 1000 can have a generally conical shape.The speculum port 1000 can be constructed from a polymer or metal alloy.The speculum port 1000 may be relatively flexible or stiff. The speculumport 1000 can include a proximal port 1002 which is removably coupled toa distal port 1004. The proximal port 1002 can be coupled to the distalport 1004 by a slight interference fit or by a threaded connection. Aninner plug 1006 can be removably and sealably coupled to the distal port1004. The inner plug 1006 includes an electrode 1008, which isconfigured as a looped electrode as shown in FIG. 2F. However, theelectrode 1008 can generally take the form of any of the electrodesdisclosed herein. The inner plug 1006 can include sealing members (notshown) configured similarly to other sealing members disclosed herein.The distal port 1004 can include an adhesive layer 1010 which may takethe form of any of the adhesives disclosed herein. The adhesive layer1010 may also be a layer of pliable silicone putty, ostomy bag adhesivegasket material, expanding foam, impression material, gel, bone wax,balloon cement, or a silicone gasket.

FIG. 10B shows an alternative distal port 1012, according to oneembodiment of the invention. The distal port 1012 is configuredsimilarly to distal port 1004, however, distal port 1012 includes anelectrode surface 1014. The electrode surface 1014 can be a layer ofmetal, such as silver, coupled to the interior surface of the distalport 1004. An inner plug 1016 can removably and sealably couple to thedistal port 1012. The inner plug 1016 can include contact surface 1018which can make electrical contact with the electrode surface when theinner plug 1016 couples to the distal port 1004.

FIG. 10C shows an alternative distal port 1020, according to oneembodiment of the invention. The distal port 1012 is configuredsimilarly to distal port 1004, however, distal port 1012 couples to aplug with a plurality of tentacle electrodes 1022. The tentacleelectrodes 1022 are highly flexible and provide increased surface area.The tentacle electrodes 1022 can include insulative and conductive areasof exposed metal.

FIGS. 10D and 10E show the speculum port 1000 in use, according to oneembodiment of the invention. The speculum port 1000 can be handled bythe proximal port 1002. The increased diameter of the proximal port 1002allows for finger manipulation and insertion of the speculum port 1000.The speculum port can be adjusted to provide visualization of thetympanic membrane. The adhesive layer 1010 on the distal port 1004provides a fluid tight seal and fixation between the distal port 1004and the ear canal. Once the speculum port 1000 has been placed in anoptimal position, the proximal port 1002 can be decoupled from thedistal port 1004. The distal port 1004 can then be filled with a drugsolution and the inner plug 1006 can be inserted into the distal port1004. The inner plug 1006 can then be supplied with electrical currentto complete the iontophoresis procedure.

FIGS. 10F through 10H show the speculum port 1000 in use, according toone embodiment of the invention. The speculum port 1000 includesalternative distal port 1012 with electrode surface 1014. The distalport 1012 has already been placed in the ear canal and the proximal port1002 has been removed, in accordance with FIGS. 10D and 10E. The distalport 1012 can be filled with a drug solution, and the inner plug 1016can be inserted into the distal port 1012. The inner plug 1016 can thenbe supplied with electrical current to complete the iontophoresisprocedure.

FIG. 11 shows a simplified support structure 1100 that is worn on thepatient's head, according to one embodiment of the invention. Thesimplified support structure 1100 is worn on the patient's head whilethe patient is awake and upright. The support structure 1100 isconfigured to hold the one or more systems described herein in alignmentwith the patient's ears E. As can be seen in FIG. 11, the supportstructure 1100 can have an alignment structure with a first body 1110engaging the first ear, a second body 1110 engaging the second ear, anda member extending around the head of the patient between the first andsecond body. Any of the earplugs of the present invention may be coupledto the head via a headset as in FIG. 11.

FIG. 12 shows a simplified support structure 1200 that is worn on thepatient's head, according to one embodiment of the invention. Thesupport structure 1200 is configured similarly to eyeglasses and can beworn in a similar fashion. Earplugs 1210 are hingably connected to thesupport structure 1200 and can be leveraged into ear canals by thesupport structure 1200. The earplugs 1210 can be configured similarly toany of the earplugs disclosed herein. The support structure 1200 canprevent unwanted movement and provide sealing force against the earplugs1210. The support structure 1200 can include adjustable elements toadjust width and length for various sized patients. The supportstructure 1200 can include visual panels, such as LCD panels which canprovide video viewing for the patient. The earplugs 1210 can alsoinclude speakers to supply audio to the patient.

The present invention may be embodied in other specific forms withoutdeparting from the essential characteristics thereof. These otherembodiments are intended to be included within the scope of the presentinvention, which is set forth in the following claims.

What is claimed is:
 1. A system for use in iontophoretic substancedelivery to a tympanic membrane of an ear of a human or animal subject,the system comprising: (a) an earplug including: (i) a distal portion;(ii) a proximal portion; (iii) a tube extending from the distal portionto the proximal portion, the tube defining a lumen; and (iv) at leastone flexible sealing element extending from an outer surface of thetube, wherein a first flexible sealing element of the at least oneflexible sealing element includes: (A) an external facing; and (B) anadhesive layer configured on the external facing; and (b) an electrodedevice including: (i) an elongate shaft, and (ii) an electrode tiphaving a diameter greater than that of the elongate shaft, the elongateshaft of the electrode device at least partially disposed within thelumen of the tube of the earplug, the electrode device being movablewithin the lumen of the tube of the earplug between a retractedposition, in which fluid can pass around the electrode device throughthe lumen, and an advanced position, in which the electrode tip contactsan inner surface of the tube to prevent fluid from flowing through thelumen.
 2. The system of claim 1, wherein the tube has a stiffness lessthan a stiffness of the proximal and distal portions of the earplug andwherein the flexible sealing element is disposed closer to the distalportion than to the proximal portion.
 3. The system of claim 1, whereinthe earplug further comprises a side vent in fluid communication withthe lumen of the tube for allowing venting of air and/or fluid from thetube.
 4. The system of claim 1, wherein the distal portion is rigidrelative to the tube.
 5. The system of claim 1, wherein the distalportion includes an o-ring, the o-ring configured to form a seal withthe electrode tip of the electrode device when the electrode device isin the advanced position.
 6. The system of claim 5, wherein an outerdiameter of the electrode tip is greater than an internal diameter ofthe o-ring, and wherein the o-ring is flexible such that the electrodetip can pass into the o-ring to form the seal.
 7. The system of claim 1,wherein the first flexible sealing element is umbrella shaped, with anopen end of the first flexible sealing element facing the proximalportion of the earplug.
 8. The system of claim 1, wherein the firstflexible sealing element is a distal sealing element, wherein a secondflexible sealing element of the at least one flexible sealing element isa proximal sealing element, and wherein a diameter of the proximalsealing element is larger than a diameter of the distal sealing element.9. The system of claim 8, wherein each of the first flexible sealingelement and the second flexible sealing element is umbrella shaped, withan open end of each flexible sealing element facing the proximal portionof the earplug.
 10. The system of claim 1, wherein the electrode deviceis malleable.
 11. The system of claim 1, additionally comprising an earhook connected with the proximal portion of the earplug, the ear hookincluding a curved member for engaging a portion of the ear andpreventing dislodgement of the earplug after placement in the ear. 12.The system of claim 1, further comprising an additional earplug and anadditional electrode device for use in iontophoretic substance deliveryto a tympanic membrane of another ear of the human or animal subject.13. The system of claim 12, further comprising a headset for couplingthe earplug and the additional earplug while they are in the subject'sears.
 14. A system for use in iontophoretic substance delivery to atympanic membrane of an ear of a human or animal subject, the systemcomprising: (a) an earplug including: (i) an elongate, flexible tubewith a proximal portion, a distal portion, and a main lumen extendingtherethrough; (ii) a first flexible sealing element shaped like anumbrella to form a seal within an ear canal, wherein the first flexiblesealing element comprises an external facing with an adhesive layer, thefirst flexible sealing element being integral to and disposed on anexterior of the elongate, flexible tube and being offset a distance froma most distal end of the distal portion of the elongate, flexible tube;(iii) a fitting coupled with the proximal portion of the elongate,flexible tube and including a side vent in fluid communication with themain lumen; and (iv) a stiffening tube located within the distal portionof the elongate, flexible tube distal to the first flexible sealingelement, the stiffening tube preventing the distal portion of theelongate, flexible tube from bending; and (b) an electrode deviceincluding: (i) an elongate shaft; and (ii) an electrode tip having adiameter greater than that of the elongate shaft.
 15. The system ofclaim 14, the earplug further comprising: (v) a second flexible sealingelement shaped like an umbrella to form a seal within the ear canal, thesecond flexible sealing element being integral to and disposed on theexterior of the elongate, flexible tube and being proximal to the firstsealing element.
 16. The system of claim 14, further comprising a kit,the kit comprising: (i) a controller connected to the electrode device;(ii) an additional earplug for another ear of the subject; and (iii) anadditional electrode device for the additional earplug, wherein thecontroller connects to the electrode device and the additional electrodedevice.
 17. The system of claim 14, further comprising a headset forplacing on the subject's head and holding the electrode device and theearplug.
 18. The system of claim 14, further comprising a drug solutionto provide iontophoretic anesthesia to the tympanic membrane of the earof the subject.
 19. The system of claim 18, further comprising a drugdelivery device for delivering the drug solution into the ear canal ofthe subject.
 20. A system for use in iontophoretic substance delivery toa tympanic membrane of an ear of a human or animal subject, the systemcomprising: (a) an earplug including: (i) a distal portion; (ii) aproximal portion; (iii) a tube extending from the distal portion to theproximal portion, the tube defining a lumen; and (iv) at least oneflexible sealing element extending from an outer surface of the tube,wherein a first flexible sealing element of the at least one flexiblesealing element includes: (A) an external facing; and (B) an adhesivelayer configured on the external facing; and (b) an electrode deviceincluding: (i) an elongate shaft, and (ii) an electrode tip having adiameter greater than that of the elongate shaft, the elongate shaft ofthe electrode device being at least partially disposed within the lumenof the tube of the earplug, the electrode device being configured toselectively allow fluid communication through the lumen of the tubebetween the distal portion and the proximal portion of the earplug, aninner surface of the tube and an outer surface of the electrode tipbeing configured to provide feedback when the electrode devicetransitions between an advanced position and a retracted position.